rfc2534.txt

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     Token with an equality relationship. Typical values include:

      letter        8.5x11.0 inches
      a4            210x297 mm
      b4            250x353 mm
      a3            297x420 mm
      legal         8.5x14 inches

   - The feature tag is intended primarily for use in the following
     applications, protocols, services, or negotiation mechanisms:

     This feature tag seems most useful for the printing application.

   - Examples of typical use:

     Choosing between a4 and letter size renditions of the same
     printable document.









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RFC 2534       Media Features for Display, Print, and Fax     March 1999


2.5 Color and greyscale

   - Media Feature tag name(s):

   color

   - ASN.1 identifier associated with this feature tag:

     1.3.6.1.8.1.6

   - Summary of the media features indicated by this feature tag:

     This feature indicates a gross level of capability to represent (or
     need for) for handling of color, out of a limited set of choices.

   - Values appropriate for use with this feature tag:

     Token with an equality relationship. Values include:

     binary      black-and-white, or other bi-level capability.

     grey        more than two levels of intensity; for example,
                 at least two bits of grey-scale data

     limited     availability of a small number of colors, such as
                 might be provided by a highlight printer, pen plotter,
                 or limited color display. Such capability is useful
                 for business graphics. At the lowest level of
                 capability, this implies at least one color other than
                 black ("highlight color"). At the high end, a small
                 number (less than 32) colors. No implication is made
                 that any particular color is available.

     mapped      pixel color values are mapped in some specifable way
                 to a multi-component color space. Sufficient levels of
                 display are available to represent a continuous tone
                 photographic image, but the result will be mapped into
                 a more limited space.

     full        ability (or at least willingness) to represent a full
                 color image and present it. Full continuous tone color
                 capability.

   - The feature tag is intended primarily for use in the following
     applications, protocols, services, or negotiation mechanisms:






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RFC 2534       Media Features for Display, Print, and Fax     March 1999


     Web applications may choose between color, grey, or binary
     representations. Fax or printing applications might choose between
     color and non-color renditions, for example.

   - Examples of typical use:

     Someone preparing a map of directions to a restaurant might prepare
     different maps for each kind of value.

   - Intended usage:

     COMMON

3. Examples of use of features

   The following examples of feature comparison show how these features
   can be used to describe various capabilities. The syntax used to
   express combinations of features is purely illustrative and not
   normative:

   pix-x<=1024, pix-y<=768
      might be used for a 1024x768 display.

   dpi=300
      might be used for a 300 dpi printer.

   paper-size=a4
      indicates the display size is 210x297mm.

4. IANA considerations

   This document calls for registration of the following feature tags,
   as per [REG]: pix-x, pix-y, dpi, ua-media, paper-size, color.  ASN.1
   identifiers should be assigned to each of these and replaced in the
   body of the registration.

5. Security Considerations

   Inaccurate media feature information ascribed to a recipient might
   cause a sender to subsequently send content that the recipient is not
   actually able to process, thus causing a denial of service.

6. Acknowledgments

   This document is based on a previous memo co-authored with Lou
   Montoulli. It had benefited from the comments of Graham Klyne, Ho
   John Lee, Brian Behlendorf, Jeff Mogul, Ted Hardie, and Dan Wing.




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RFC 2534       Media Features for Display, Print, and Fax     March 1999


7. References

   [REG] Holtman, K., Mutz, A. and T. Hardie. "Feature Tag Registration
         Procedures", BCP 31, RFC 2506, March 1999.

   [SI]  ISO 1000:1992 "SI units and recommendations for the use of
         their multiples and of certain other units", International
         Organization for Standardization, 1992.

Authors' Addresses

   Larry Masinter
   Xerox Corporation
   Palo Alto Research Center
   3333 Coyote Hill Road
   Palo Alto CA 94304

   Fax [phone]
   EMail: [e-mail]


   Dan Wing
   Cisco Systems, Inc.
   101 Cooper Street
   Santa Cruz, CA 95060  USA

   Phone: [phone]
   Fax:   [phone]
   EMail: [e-mail]


   Andrew H. Mutz
   Jutvision Corporation
   124 University Avenue Suite 202
   Palo Alto CA 94301

   Phone: [phone]
   Fax:   [phone]
   Email: [e-mail]


   Koen Holtman
   Technische Universiteit Eindhoven
   Postbus 513
   Kamer HG 6.57
   5600 MB Eindhoven (The Netherlands)

   EMail: [e-mail]



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RFC 2534       Media Features for Display, Print, and Fax     March 1999


Full Copyright Statement

   Copyright (C) The Internet Society (1999).  All Rights Reserved.

   This document and translations of it may be copied and furnished to
   others, and derivative works that comment on or otherwise explain it
   or assist in its implementation may be prepared, copied, published
   and distributed, in whole or in part, without restriction of any
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   The limited permissions granted above are perpetual and will not be
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   This document and the information contained herein is provided on an
   "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
   TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
   BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
   HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
























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